This issue, which completes volume 8 of the Handbuch, opens with an excellent general article on the rickettsiae by Rocha Lima, who first designated this group of organisms by its present name. The Japanese investigator Kawamura contributes an article on tsutsugamushi disease, the peculiar continued eruptive fever transmitted by the bite of certain Asiatic mites. The greater part of this issue is taken up with a discussion of herpes zoster and encephalitis by Doerr and Berger. The authors discuss with much elaboration the vexed question of the relations between herpes and encephalitis. The problem of postvaccinal encephalitis is also fully considered without, however, any definite conclusion as to the cause of this singular and disturbing ailment. Measles and mumps are dealt with as diseases of uncertain etiology. The writers conclude that none of the microorganisms yet described as associated with measles can be regarded as surely the causal agent. Mumps,